I'd seen them in stores but was told about a year ago that they only work on specific machine...one ad I just saw online indicated that it fits Huskvarna/Pfaff. Heres is text from one of the ads...
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First Introduced as Fabric Mover and Fab U Motion for $1000+USD, Free Motion Assistant is now only 1/3 of the original retail price that Husqvarna Viking and Pfaff dealers had charged.
Works with Pfaff creative 2170, 2144, 2140, 2134, 2124; performance 2056, performance 2054; quilt expression 2048, quilt expression 2046, quilt expression 2044, expression 2038, expression 2036, expression 2034, classic style fashion 2023, classic style 2025, classic style quilt 2027, classic style home 2029. There will be a different feel and there are different reactions in the different models because of different motors in these machines.
This model is identical to the Pfaff Fabric Mover with Stitch Regulator (820 78 10-96) and the original Husqvarna Viking Fabric Mover with Stitch Regulator (920 12 20-96).
Small Fabric Mover for free motion quilting on your sewing machine. This handy platform slides on top of the arm of the sewing machine and supports the fabric while you move the platform.
Comes with Quilter's Cruise Control stitch length regulator for use with machines listed above.